Best one I've heard is to take out the vacuum cleaner and leave it in your hallway or by the front door. When people come to visit you can say, 'Oh, I was just about to clean up'. From that point on you can live in squalor, and if you have really lovely friends/family they should offer to do it for you!

PS/ Two favourite books of mine to add to the list: 'What I Loved' by Siri Hustvedt (though I see it's got another fan) and 'numberninedream' by David Mitchell.